Android-使用AndroidTrack播放PCM音频

Android中，利用AndroidTrack可以直接播放PCM音频。

代码如下：

package com.baidu.carlife;

import android.media.AudioFormat;
import android.media.AudioManager;
import android.media.AudioTrack;

public class MyAudioTrack {
	
    int mFrequency;// 采样率 
    int mChannel;// 声道 
    int mSampBit;// 采样精度 
    AudioTrack mAudioTrack;
    
    public MyAudioTrack(int frequency, int channel, int sampbit){ 
            mFrequency = frequency; 
            mChannel = channel; 
            mSampBit = sampbit; 
    }
    
    public void init(){ 
    	if (mAudioTrack != null){ 
    		release(); 
        } 

		if (mSampBit == 8)
			mSampBit = AudioFormat.ENCODING_PCM_8BIT;
		else
			mSampBit = AudioFormat.ENCODING_PCM_16BIT;

		if (mChannel == 1)
			mChannel = AudioFormat.CHANNEL_IN_MONO;
		else
			mChannel = AudioFormat.CHANNEL_IN_STEREO;
		
    	int minBufSize = AudioTrack.getMinBufferSize(mFrequency,  mChannel, mSampBit); 

    	mAudioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, mFrequency, mChannel, mSampBit, minBufSize, AudioTrack.MODE_STREAM); 
    	mAudioTrack.play();         
    } 
    
    public void release(){ 
        if (mAudioTrack != null){ 
        	mAudioTrack.stop();                                                
            mAudioTrack.release(); 
        } 
    } 
     
    public void playAudioTrack(byte []data, int offset, int length){ 
    	if (data == null || data.length == 0){return ;} 
        try { 
        	mAudioTrack.write(data, offset, length); 
        } catch (Exception e) { 
        	e.printStackTrace();
        } 
    } 
     
    public int getPrimePlaySize(){ 
    	int minBufSize = AudioTrack.getMinBufferSize(mFrequency, mChannel, mSampBit);
        return minBufSize * 2; 
    } 
}

调用的时候，只需要：

MyAudioTrack  audioTrack = new MyAudioTrack(rate, channel, bit);
audioTrack.init();
byte[] resultData = new byte[length];
audioTrack.playAudioTrack(resultData, 0, resultData.length);